Archaeological spatiotemporal map

So I have been trying to use Time Manager to make a spatiotemporal map of artefacts found on a archaeological site. My goal is to show if there is areas on the site wich concentrates artefacts having the same chronology and then to show how it is changing in time.

So I have a vector layer based on a .csv containing attributes like this for example.

Bronze sword / X coordinate / Y coordinate / 99-01-01 (start) / 140/01/01 (end)

everytime I press play i got something like that :

Traceback (most recent call last): File "/Users/Antoine/.qgis2/python/plugins/timemanager/timemanagercontrol.py", line 314, in playAnimation stepFunction() File "/Users/Antoine/.qgis2/python/plugins/timemanager/timemanagercontrol.py", line 353, in stepForward self.timeLayerManager.stepForward() File "/Users/Antoine/.qgis2/python/plugins/timemanager/timelayermanager.py", line 222, in stepForward self.setCurrentTimePosition(self.getCurrentTimePosition() + self.timeFrame()) File "/Users/Antoine/.qgis2/python/plugins/timemanager/timelayermanager.py", line 217, in setCurrentTimePosition self.refreshTimeRestrictions() File "/Users/Antoine/.qgis2/python/plugins/timemanager/timelayermanager.py", line 136, in refreshTimeRestrictions timeLayer.setTimeRestriction(self.getCurrentTimePosition(),self.timeFrame()) File "/Users/Antoine/.qgis2/python/plugins/timemanager/timevectorlayer.py", line 193, in setTimeRestriction self.getDateType(), date_format=self.getTimeFormat(), query_idiom=idiom) File "/Users/Antoine/.qgis2/python/plugins/timemanager/query_builder.py", line 109, in build_query sub1=create_ymd_substring(ioy,iom,iod,from_attr,quote_type='"') # quote type for column File "/Users/Antoine/.qgis2/python/plugins/timemanager/query_builder.py", line 71, in create_ymd_substring ystr = "SUBSTR({}{}{},{},{})".format(q,col,q, ioy+1,ioy+5) if ioy>=0 else None # adding 1 UnicodeEncodeError: 'ascii' codec can't encode character u'\u017d' in position 6: ordinal not in range(128)

I'm new to QGIs so I dont really now what it means...

It would be really interesting if we could manage to make Time Manager work for archaeological use!

Thank you for your help and work

Antoine